Apparatus for agitating cleansing liquid



Nov. 22, 1960 M. R. BLAND 2,960,991

APPARATUS FOR AGITATING CLEANSING LIQUID Filed July 25, 1958 4 Sheets-Sheet 1 MRSA/ALL H BLA/v0 INVENTOR.

Nov. Z2, 1960 M. R. BLAND 2,960,991

APPARATUS Foa AGITATING CLEANSING LIQUID med July 25, 195s 4 sheets-sheet 2 MARSHALL R BLA/v0 INVENTOR.

Nov. 22, 1960 M. R. BLAND APPARATUS Foa AGITATING cLEANsING LIQUID 4 Sheets-Sheet 3 Filed July 25, 1958 MRSA/ALL RELA/vo INVENTOR. BY

Nov. 22, 1960 Filed July 25. 1958 M. R. BLAND APPARATUS FOR AGITATING CLEANSING LIQUID )1424 @SHA/ L H. BL AND INVENTOR.

BYWWM A 7- raR/VE Y6 APPARATUS FOR AGlTATING CLEANSING LIQUID Marshall R. Bland, La Habra, Calif., assigner to Turco Products, Inc., Los Angeles County, Calif., a corporation of California Filed July 25, 1958, Ser. No. 750,965

1S Claims. (Cl. 134-182) This invention relates generally to improved cleansing apparatus of the type employing liquid subject to mechanical agitation so as to improve the cleansing efficiency of the liquid resulting from its contact with soils to be removed frorn parts inserted within a liquid receptacle. More particularly, the invention concerns the construction and design of cleansing apparatus in which screw propellers are rotatable in the liquid receptacle and in such relation to recessed opposite sides of the receptacle as to displace and guide the liquid flow in high velocity cleansing relation with soiled articles placed within the receptacle.

In the past it has been generally known that agitation of a cleaning solution improves the parts cleansing efciency of the solution, and to serve this purpose apparatus has been built in winch agitating means was placed at the bottom of a tank for agitating the liquid in a continuous undirectional ow pattern below soiled parts placed in the tank. While some improvement in cleansing eiiiciency resulted from the use of such known apparatus, it was found that the degree of improvement was low in relation to the amount of mechanical energy imparted to the liquid by the agitating means, and it is a major object of the present invention to so construct cleansing apparatus that the soils removing efficiency of the agitated solution Will be greatly improved in relation to the amount of energy imparted to the liquid.

ln carrying out the above object, the invention contemplates agitation of the solution in such manner that it moves with high velocity tangentially and also normal to soils carrying surfaces of the parts to be cleaned, thereby promoting the cleansing effect, both mechanical and chemical, resulting from moving Contact of the solution against the soils. Such high velocity directed agitation is secured in the rectangular cleansing Zone through the use of propellers rotatable in side recesses in a parts receiving receptacle to displace liquid at high velocity axially through the propellers and in a viscous and streamlined flow pattern everywhere along the recessed and flat sides of the receptacle, for effecting continuous and directed circulation of the liquid in high velocity cleansing relation with articles received in the receptacle cleansing zone. lt is an important feature of the invention that means are provided for periodically reversing the propellers in desired relation so as to secure a reversal in the direction of -liquid displacement within the cleansing zone, having the effect of alternating the liquid impingement and shearing effects on soils carried by the parts exposed to the high velocity circulating liquid in the cleansing zone.

Another important feature of the invention concerns the provision of recesses in the sides of the tank, and particularly in the form of truncated pyramids having divergent sides for guiding the liquid circulation produced by rotation of the propellers in streamline relation to the top, bottom and opposite sides of the receptacle. Such circulation is eected axially through the propellers and in a viscous or laminar, as opposed to turbulent, ow

atent O rice pattern along the sides of the receptacle, with the result that the liquid flows with maximum velocity in the cleansing zone. Each of the recesses preferably has a pair of vertically spaced sides diverging to the top and bottom of the receptacle and particularly to top and bottom baffles therein for guiding the flow in a pair of vertically spaced -loops through the liquid cleansing zone. Likewise, the two remaining horizontally spaced recess sides form the ilow into horizontally spaced loops passing through the cleansing zone, so that associated with each recess and propeller there are preferably four liquid ow loops circulating respectively along the top, bottom and opposite side walls of the receptacle, and merging in the cleansing zone, the direction of tiow in any of these loops depending upon the direction of rotation of the propellers. As will appear, such controlled high velocity circulation of the `liquid achieves maximum soils cleansing efficiency as respects the parts received Within the cleansing zone, which is preferably rectangular both in horizontal and vertical cross sections for receiving a rectangular parts basket.

Another object of the invention includes the provision in the above described cleaning tank o-f a settling zone at the bottom of the tank arranged so that insoluble soils removed from parts inserted within the tank by liquid flowing in loop-ing configuration therein are adapted to settle out into the settling zone during liquid circulation in the tank. In addition, the invention contemplates the provision of a novel liquid baliiing arrangement for confining the cleansing yliquid in the cleansing zone of the tank, and also for separating that liquid from an overlying liquid seal operable to prevent escape of volatile cleansing liquid upwardly from the tank.

These and other objects and advantages of the invention, as well as the details of an illustrative embodiment, will be more fully understood from the following detailed description of the drawings, in which:

Fig. l is a side View of one form of the cleaning apparatus showing the receptacle partly broken away to illustrate the interior construction thereof, and the liow of liquid therein;

Fig. 2 is an end elevation of the exterior of the receptacle;

Fig. 3 is a View taken on line 3 3 of Fig. l;

Fig. 4 is a view taken in elevation showing a modified soils entrapment zone at the bottom of the tank and a perforated baiiie separating that zone from the cleansing zone thereabove;

Fig. 5 is a view taken in elevation and shows the baiiie of Fig. 4 in raised position;

Fig. 6 is a View taken in elevation and shows a modified baffling arrangement above the cleansing Zone together with mechanism for moving the baiing;

Fig. 7 is a plan view through a modified tank showing multiple screw propellers at opposite sides thereof;

Fig, 8 is a plan view of a modified rectangular tank having screw propellers at each of the four sides of the tank;

Fig. 9 is a schematic elevation of the interior of a cleansing receptacle incorporating the invention and showing one liow path of liquid therein;

Fig, l0 is a view similar to Fig. 9 showing an alternate flow path of cleansing liquid;

Fig. ll is a view similar to Fig. 9 showing another alternate iiow path of cleansing liquid; and

Fig. l2 is still another view similar to Fig. 9 showing yet another possible iiow path of the liquid.

Referring first to Figs. l through 3, the cleansing apparatus 10 includes an upright tank 11 which has opposite front and rear walls 12, and opposite walls 13 together forming an interior zone 14 for receiving articles to be cleansed. Typically, such articles-may comprise 'lined and not turbulent.

3 jet engine parts such as illustrated at as retained in a rectangular basket 16 received downwardly between the receptacle walls into the cleansing zone 14. The basket is shown as seated on a grating 17 typically having an -egg-crate'design andconsisting of two sets of integral panels extending vertically and at right angles to one an- ,other to form spaces 18 therebetween into which soils removed from the parts 15 are adapted to settle out of the path of liquid circulation in the receptacle.

The opposite walls 12 of the tank have recesses 19 formed therein which open transversely and divergently .toward the cleansing zone 14. Each of the recesses is preferably in the form of a tuncated pyramid having four divergent sides, a vertically spaced pair 20 of which di- 'verge respectively toward the top and bottom of the receptacle. Similarly, a horizontally spaced pair 21 of the recess sides diverge respectively toward the opposite sides 13 of the receptacle, and it will be understood that as a result of this recess configuration the liquid is circulated 'in the tank in four loops which merge in the central regions of the cleaning zone, as indicated by the arrows in Figs. l and 3.

Such liquid circulation is preferably eilected by a hy- .drodynamically designed and reversible thrust thrust propeller 22, typically a three blade screw propeller, oper- =able to displace the bulk of the liquid therethrough and .alternately in axially opposite directions, as distinguished from the action of a centrifugal impeller which throws the bulk of the liquid radially therefrom during impeller rotation and moreover is not reversible to displace liquid Vin opposite directions as desired. Each propeller is at- VYtachedto a horizontally extending shaft 23 projecting through the wall 12 at its ilat square head or base 24 from which diverge the upwardly and downwardly ilared :wall portions 20 and the horizontally ilared portions 21 Yof the receptacle wall 12. Attached to the base 24 is the housing 28 of an electric motor, which is preferably re- .versible so that the propeller 22 may be driven in opposite directions. Each of these motors may be of the Yinduction type, so that by changing the polarity of the motor or the phase relationship of the applied current VVa reversal in the direction of the drive transmitted to the lpropeller maybe secured. Current is applied to each V`motor through switching mechanism indicated at 30 which is operable to reverse the direction of drive transmission .to the propellers from the motors, for purposes to be described. A master control switch is shown at 130.

In operation the liquid filling the tank is caused to be ycirculated by the opposed propellers, which have a common horizontal axis of rotation as shown in Fig, l, such circulation being indicated by the arrows. When the propellers are rotated so as to displace liquid axially therethrough, the liquid ilows radially in a laminar` or viscous flow pattern in each of the recesses 19 adiacent the ared wall portions 20 and 21. Since those wall portions flare outwardly to the top, bottom and opposite sides of the receptacle, the ilow pattern therealong is stream- Furthermore, each propeller is spaced at a distance from the head or base 24 substan- VIVtially equal to the diameter of the propeller, it having been found that this dimensional relationship is most desirable from the standpoint of the viscous or laminar ow kpattern desired.

As the liquid leaves the recess 19 in the four loops indicated by the arrows in Figs. lV and 3, it circulates through the cleansing zone 14 inthe symmetrical ilow pattern shown by the arrows, which assumes that opposite .propellers Aare being Vrotated to displace liquid axially therethrough toward the heads or bases 24 and away from the cleansing zone. Such circulation is reversible by reversing the direction of propeller rotation to secure alternation of the impingement and shear eiects of the vilowing high velocity liquid upon the soils coating the parts to be cleaned. Also, opposite propellers may be rotated so that the liquid circulates as shown in Fig. 7, tlowing completelyV across the tank from propeller to d propeller. Under these conditions, the liquid passes through both propellers in the same direction, whereas in Fig. l the liquid passesthrough opposite propellers in opposite directions.

Shown in the upper regions of Fig. l and also in Figs. 2 and 3 is a split cover o r baille 32 extending in a horizontal plane and overlying the cleansing zone 14 Within the tank or receptacle. The cover halves are guided in tracks 33 soas to be slidable transversely outwardly away from the receptacle, leaving the cleaningzone exposed for downward reception of the parts basket 1,6. Fig. 2 shows a plate type heating element 35 secured to the inner side of the receptacle ilared wall portion 21 for heating the liquid therein to desired temperature for maximum cleaning eillciency, typical cleaning liquids consisting of trichloroethylene, cyclohexane, and solutions of detergents, or acids or bases, such as strong caustic solutions. Representative soils or parts such as bearings, shafts, compressor blades, sleeves and the like include greases, oils, dust, tar, sludge, rust, resin, wax, carbon, lapping and builing compounds, and steel particles.

The tank shown in Figs. l to 3 has a sloping bottom tapering downwardly and away from the grating 17 to form a ilow space 81 within which collected soils may ilow laterally to the normally closed outlet 82. Liquid is typically supplied to the tank through an inlet 83 in wall 13 below the level of the cover 32.

Fig. 4 shows a cleaning tank or receptacle 11 having having a cleaning zone 14 separated from a soils collection zone 54 therebelow by a perforated false bottom baille plate 55. The latter is hinged at 56 at one side of the receptacle and supported at 57 at the opposite side of the receptacle, with the baille plate extending horizontally so that liquid may ilow thereover with minimum resistance. Soils separating out onV the baille 55 are carried downwardly through the perforations therein into the collection zone 54 by a side stream of the ilowing liquid, which then returns upwardly through plate perforations into the main stream of liquid ilow in the cleansing zone, as indicated by the arrows. The baille plate is shown in lifted position in Fig. 5, giving access to the soils collection zone for cleaning it at regular intervals, the cover 37 of the tank having been removed. Y V In Fig. 6 there is shown a pair of bailles 60 each comprising parallel metal slats 61 hinged together at 62 along their lengthwise dimensions so that the bailles may be bodily displaced between extended horizontal position overlying the cleansing Zone and into vertically retracted position at opposite sides of that zone. As illustrated, the opposite ends of the slats are guided in track units 63 extending vertically and horizontally and attached to the inner sides of the tank or receptacle walls 12. The slats may have gaps therebetween for receiving the teeth 65 of driving sprockets 66, a suitable drive system for the sprockets being provided. Typically such a system will .include a motor 67 outside the receptacle driving a Worm 68, which engages a gear 69 on a shaft 70, the latter driving the sprockets 66 through bevel gears 71. The hailles 60 illustrated are of the so-called leaking type, that is they will permit escape of gaseous pressure from the cleansing zone. Thus, should steam form therein it will escape upwardly through the baille while at the same .time the latter prevents excessive upward escape of agitated cleansing liquid from the tank during a cleansing operation. Furthermore, the baille system illustrated in Fig. 6 may be used for separating the liquid in the cleansing zone from a sealing liquid layer in the region above the baille. Corrosion inhibitors such as potassium chromate in the liquid seal, which typically comprises water, may then wash slowly downwardly through the baille into the cleansing solution, there being suilicient circulation between the latter and the liquid seal to permit such slow washing of the corrosion inhibitors into the cleansing solution. Y

Y Turning now to Fig. 7, the recessed wall of the elongated receptacle therein shown contains two recesses 19, with a propeller in each'recess opposite a similar propeller in the opposite recessed wall of the receptacle. As shown, the design of the receptacle, propellers and recess walls 19 is the same as previously described, with the exception that the receptacle is much longer, accommodating an elongated parts basket 73 within which long jet parts are typically receivable. Vertical ways 74 at opposite sides of the receptacle andA between the recesses at each side of thelatter are adapted to receive a divider illustrated at 75 for dividing the cleansing zone and receptacle in two parts, each of which is substantially the same as viewed in Figs. 1 through 3.

The propellers are rotatable to circulate the liquid typically as viewed in Fig. 7, so that it travels at high velocity across the tank or receptacle from propeller to propeller. Under these conditions, the liquid is displaced axially through both propellers in the same direction.

The directions of propeller rotation may be reversed at intervals to travel the liquid through both propellers in 4the same directions as schematically seen in Figs. 9 and 10. Also the propellers may be rotated so that the liquid instead of passing therethrough in the same direction passes through opposite propellers in opposite directions under which conditions the liquid ilow in the central regions of the tank will be turbulent due to the interference of the flow directed toward the center of the receptacle from each recessed side thereof. Figs. 11 and l2 respectively illustrate schematically the liquid flow pattern when the liquid is passed through both propellers toward the sides of the receptacle and alternately toward the center thereof. Reverse shear and impingement ow directions of the liquid is illustrated by the arrows in the broken line sections 80 of the cleaning zones associated with Figs. 9 through 1l.

Fig. 8 shows another modified rectangular tank construction in which all four opposite sides of the receptacle are similarly oppositely recessed as at 19, with a propeller in each recess. As shown, opposite propellers 76 are rotated so as to circulate liquid axially toward the center of the receptacle, whereas opposite propellers 77 are rotated so as to circulate liquid oppositely away from the center of the tank, the resulting ow pattern oomprising the four circulation loops 78. Upon reversing rotation of the pairs of propellers, the directions of the arrows designating these loops will likewise be reversed, to achieve the high etliciency alternate shear and impingement cleansing action desired.

Referring again to Figs. 9 through l2, a typical cycle of operation will include rotation of the propellers to displace the liquid axially as seen in Fig. 9 for 21/2 minutes, following which one of the propellers will be reversed and operation continued for another 21/2 minutes. At the end of this time the other propeller is reversed, and nally after the end of 21/2 minutes the first propeller is again reversed to complete the cycle. As a result, the cycle will incorporate in sequence the low patterns illustrated in Figs. 9, l2, l1 and l0` involving reversal of the right side propeller at the end of every interval of 21/2 minutes duration and reversal of the left side propeller at the end of 5 minute intervals, providing for alternating the normal impingement and tangential shear effects of the liquid on the soils, as indicated by the arrows contained within the broken line sections 80 of the cleaning zones shown in Figs. 9 through l2.

I claim:

l. Improved cleansing apparatus, comp-rising an upright receptacle forming an interior zone for receiving articles to be cleansed by liquid circulating therethrough, said receptacle having opposite sides forming recesses opening transversely and divergently toward said zone, said recesses each being in the form of a truncated pyragnid and said receptacle sides each flaring toward the top 6 and bottom of Ithe receptacle, and propellers in said re'- cesses operable to draw liquid inV high velocity courses of ilow transversely from within the interior of said zone toward said recesses and to return liquid in high velocity courses of ilow transversely away from said recesses toward the interior of said zone.

2. Improved cleansing apparatus, comprising an upf right receptacle having front, rear and side walls and forming an interior zone for receiving articles to be cleansed by liquid circulating therethrough, said front and rear walls forming recesses opening transversely and divergently toward said zone, each recess being in the form of a ltruncated pyramid and each recessed wall having four portions llaring respectively toward the top, bottom and said opposite sides of the receptacle, a screw propeller in each recess spaced from the receptacle recessed wall and rotatable about a central axis therein extending substantially horizontally toward said zone to draw liquid in a lirst high velocity course of ilow transversely from Within the interior of said zone toward said recess and to return liquid in a second high velocity course of llow transversely away from said recess, said propeller being operable to displace liquid at high velocity axially through the propeller and in a viscous llow pattern along said recessed wall, and means for rotating each propeller in opposite directions about its axis of rotation -to reverse the directions of liquid displacement within said zone.

3. The invention as dened in claim 2 in which recesses in said receptacle front and rear walls are horizontally opposed.

4. The invention as dened in claim 3 comprising at least two laterally spaced apart recesses in each front and rear wall of the receptacle.

5. The invention as defined in claim 2 in which each screw propeller is wholly conllned within said recess, and including a carrier for said articles removably received downwardly within said zone.

6. The invention as dellned in claim 5 including a bale directly overlying said zone and toward which each recessed wall of lthe receptacle llares upwardly.

7. The invention as defined in claim 6 in which said baille is perforate.

8. The invention as dened in claim 7 including baille guides extending vertically and horizontally within said receptacle, said baille being movable along said guides between horizontally extended position overlying said zone and vertically retracted position at the interior side of lthe receptacle, and means for so moving said baille.

9. The invention as dened in claim 5 including a support for said carrier underlying said zone and toward which each recessed wall of the receptacle llares downwardly.

10. The invention as defined in claim 9 in which said support comprises a grate having horizontally extending cross members for trapping therebetween soils removed from said articles and settling from said liquid traversing the top of the grate.

l1. The invention as defined in claim 9 in which said support comprises a perforated plate overlying a soils collection zone in the receptacle and within which soils removed from said articles are separated from liquid flowing downwardly through said plate perforations.

12. The invention as dened in claim 2 in which said propeller rotating means comprises an electric motor outside the receptacle and a motor driven shaft projecting horizontally through the receptacle recessed wall into said recess.

13. Improved cleansing apparatus, comprising an upright receptacle having opposite side and end walls and forming an interior zone for receiving articles to be cleansed by liquid circulating therethrough, said opposite side and end walls forming recesses opening transversely and divergently toward said zone, each recess being in lthe form of a truncated p ramid and each recessed Wall jliaving four portions aring respectively toward vthe top, bottom and adjacent upright Walls of the receptacle, a

fzone toward said recess and to return liquid in a second high velocity course of flow transversely away from said frecess, said propeller being operable to displace liquid at vhigh velocity axially through the propeller and in a viscous ow pattern along said recessed wall, vand means for rotating each propeller in opposite directions about lits axis of rotation to reverse the directions of liquid displacement within said zone.

14.A Improved cleansing apparatus, comprising an upright receptacle forming an interior zone for receiving articles to be cleansed by liquid circulating therethrough, said receptacle having opposite sides at least one of which forms Va recess opening transversely 'and divergently toward said zone, said recess being in the form of a truncated pyramid andv lsaid recessed sides fiaring toward the ltop, andbott'omo'fthe receptacle,v and a propeller in said/recess'operable'to draw liquid in a high velocity course of ow transverselyl from Within the interior of vsaid zone toward said recess and to return liquid in a high velocity course of ow transversely away from said recess toward theV interior of said zone.

n 15. The invention as `deined in claim 14 including means for rotating said propellerin opposite ydirections to reverse the 'directions of liquid displacement within References Cited in the 'iile of this patent y UNITED STATES PATENTS 855,071

smith Mayas, 1907 2,395,747 "Loeb Feb. 7.6,v 1946 ,Gibsonl Aug. 9, 1949 

